Merck's Keytruda Fails to Meet Primary Endpoint in Phase 3 KEYNOTE-585 Trial for Locally Advanced Gastric and Gastroesophageal Junction Adenocarcinoma

Intelligent Finance APP learned that Merck & Co., Inc. (MRK.US) announced on Tuesday that its Phase 3 KEYNOTE-585 trial for Keytruda and chemotherapy in the treatment of gastric cancer, as well as gastric and gastroesophageal junction (GEJ) adenocarcinoma, did not meet the primary endpoint.

This randomized, double-blind trial involving more than 1,000 patients aims to evaluate anti-PD-1 therapy combined with chemotherapy as a neoadjuvant treatment for locally advanced resectable gastric adenocarcinoma and GEJ adenocarcinoma.

After the neoadjuvant period, patients received Keytruda plus chemotherapy as adjuvant treatment, followed by Keytruda monotherapy.

MSD stated after a pre-specified interim analysis that while the primary endpoint of event-free survival (EFS) in the Keytruda group showed improvement, the results were not statistically significant.

However, KEYNOTE-585 achieved one of its primary endpoints of pathological complete response (pCR) rate, indicating a statistically significant improvement in pCR compared to chemotherapy alone.

After the disappointing EFS endpoint data, researchers have not yet evaluated the overall survival (OS) endpoint.